@Márcio20 Airbnb makes the determination as to whether a cancellation meets this criteria and will ask the person making the cancellation for documentation, if they need it (in some cases, the documentation may not be necessary, as when there is a natural disaster in the area, or an area has closed its borders due to Covid restrictions, which Airbnb is aware of), but they do not share this documentation with users.
This works both ways- if a guest cancels due to what Airbnb accepts as force majeure, they don't share the documentation submitted with hosts.